A screengrab of an advert that was shown during the World Cup.
Photograph: 101 Great Goals

British World Cup viewers were exposed to almost 90 minutes of betting adverts during the tournament prompting claims that children are being bombarded with messages encouraging them to gamble.

From the beginning of the tournament to England’s semi-final clash with Croatia, ITV carried more than eight and a half hours of advertisements, of which just under an hour and a half were advertising betting.

That is equivalent to 17% of World Cup ad breaks, or roughly one minute in every six, with the 172 betting spots combined lasting nearly the length of a football match.

Bookmakers and online casino companies enjoyed one and a half times as much screen time as alcohol firms and almost four times that of fast food outlets.

A government review of gambling regulation published earlier this year shied away from suggesting curbs on gambling adverts, citing insufficient evidence that adverts for betting were causing harm to children and vulnerable people.

But Labour’s deputy leader, Tom Watson, and the charity GambleAware said this was partly due to a lack of funding for research into gambling adverts since they were deregulated in 2007, under Tony Blair’s government.

“One of the only downsides to this brilliant World Cup has been the bombardment of gambling advertising on TV and social media that thousands of children will have been exposed to,” said Watson.

“With an estimated 25,000 children under 16 addicted to gambling, there is nowhere near enough work being done to study the effects of this advertising.

“Instead of confronting this issue in the most recent gambling review, the government has turned a blind eye. In doing so they’ve let our children down.”

Watson added that Labour would impose a mandatory levy on the industry to fund increased research, education and treatment of gambling addiction and the effects of advertising.

GambleAware, funded via a voluntary levy on gambling firms of 0.1% of revenue, has backed a mandatory tax because it does not receive enough money to fund research and treatment for problem gamblers, estimated to number more than 400,000 in the UK.

It has only recently commissioned the first major piece of research, conducted by the University of Stirling and Ipsos Mori, into the effects of gambling ads being deregulated more than 10 years ago. The studies are not due to be complete until next year.

The GambleAware chief executive, Marc Etches, said: “In the absence of evidence, the concern is that this is an adult activity and young people are growing up with it being normalised.

“They get exposed to it on television around sports, advertising online and gambling activities within [computer] games.

“It seems to have gone too far. And for young people growing up there just seems to be a stronger and stronger affiliation between the two [gambling and sport] and I’m wary of that.”

Fiona Dobbie, who is leading the University of Stirling’s research into gambling ads, said the study would analyse the response of children and other vulnerable groups to marketing.

“This is very much a starting point and we hope it will make a positive contribution to future legislation and policy to protect children from gambling-related harm,” she said.

“If we’d had something starting then [2007], we’d have much robust data but we’re now 10 years down the line.”

According to ITV, nearly 30 million people watched England’s semi-final clash with Croatia. This increased the cost of gambling advertising on the channel because it allowed companies to reach so many people.

Advertising industry sources said a 30-second spot during the semi-final of the World Cup could cost as much as £350,000 but that bookmakers and online casinos were paying a premium to secure blanket coverage.

The Guardian analysed more than 1,300 adverts that were shown around the first 30 games shown by ITV in the competition. Of those, 172 were betting adverts or one in eight commercials. Excluding the sponsored adverts shown at the beginning and end of each break, betting accounted for one in six adverts shown during the broadcaster’s World Cup coverage.

The Advertising Standards Authority said it had received 115 complaints about World Cup gambling adverts, mostly about their sheer volume, compared with just 27 in the previous month.

The regulator is also examining several adverts that offer improved odds for a short period, to see if they contravene new guidance in the advertising code of practice that bars companies from making urgent calls to action.

In the UK, gambling companies are only permitted to advertise before the 9pm watershed if they do so during live sporting events.

The stipulation is in stark contrast to the law in Australia, where gambling adverts attached to live sports were banned earlier this year.

Methodology: The Guardian recorded the duration of every advertisement shown during ITV’s World Cup coverage, specifically, the ad break prior to and after the national anthems, the two half-time ad breaks and that directly after the game ending. Where the match went to extra time and/or penalties the analysis was extended to include the ad break shown directly after the match was decided.